16results about How to "Improve cycle retention" patented technology

The invention provides a silicon-carbon negative electrode material, a preparation method thereof, negative electrode slurry, a negative electrode plate and application. The invention provides a preparation method of a silicon-carbon negative electrode material, which comprises the following steps: S1, mixing linear phenolic resin with an organic solvent, sequentially adding urotropine, carbon nanotubes, a defoaming agent and polycarbosilane, and mixing to form a mixture; s2, drying, cross-linking, carbonizing, activating and cooling the mixture to obtain a porous carbon material; s3, silane mixed gas is introduced into the porous carbon material, silane deposited porous carbon is obtained through deposition, then acetylene mixed gas is introduced, nitrogen is introduced after acetylene deposition, and the silicon-carbon negative electrode material is obtained through cooling; wherein the polycarbosilane is a compound as shown in a formula I, and n ranges from 1000 to 2000. According to the negative electrode material prepared by the method, the mesoporous strength is improved, the expansion coefficient is reduced, the cycle retention rate of the battery is improved, and the service life of the battery is prolonged. # imgabs0 #

The invention relates to the technical field of batteries, in particular to a surface-modified positive electrode material and a surface modification method thereof. The positive electrode material surface modification method provided by the invention comprises the following steps: S1, mixing a cobalt source with an organic solvent to obtain an intermediate, and depositing the intermediate on a graphite sheet by adopting a chemical deposition method to obtain a coating material; and S2, mixing the positive electrode material with the coating material obtained in the step S1, and calcining to obtain the surface-modified positive electrode material. According to the invention, the cobalt source is deposited on the graphite flake through a chemical deposition method to form the graphite flake of which the surface is uniformly coated with cobalt hydroxide, so that not only can the stability of the coating material structure be improved, but also the electrochemical activity of cobalt hydroxide in the coating material can be further improved; the graphite flake with cobalt hydroxide deposited on the surface is used as a coating material to be sintered with the positive electrode material, so that the obtained surface-modified positive electrode material is good in structural stability and high in specific capacity, and the cycle retention rate of the battery can be improved.

The invention provides a thick electrode plate without residual multi-step holes, a preparation method of the thick electrode plate and a lithium ion battery. According to the preparation method, the current collector is obtained; sequentially carrying out n times of coating operation on the slurry; the slurry for the first coating operation does not contain ammonium bicarbonate solid particles; slurry from the second coating operation to the nth coating operation contains ammonium bicarbonate solid particles, and the use amount of the ammonium bicarbonate solid particles used in each coating operation is increased along with the increase of the coating operation times; and sequentially carrying out drying operation and rolling operation on the slurry after each coating operation, so that the ammonium bicarbonate solid particles are gasified during drying, and the obtained non-residue multi-stepped-hole thick electrode plate forms a down-gradient-difference porous structure. According to the preparation method, the characteristic that the ammonium bicarbonate solid particles are easy to decompose at low temperature and free of residues is utilized, on the premise that it is guaranteed that the porous structure along the gradient difference is prepared, the phenomenon that the coating is prone to cracking in the drying process is avoided, and drying energy consumption is reduced.

The invention provides an organic-inorganic hybrid solid-state polymer electrolyte coated high-nickel positive electrode material as well as a preparation method and application thereof, and relates to the technical field of all-solid-state lithium batteries. The high-nickel positive electrode material coated with the organic-inorganic hybrid solid polymer electrolyte comprises an inner core and an organic-inorganic hybrid coating layer coated on the surface of the inner core, the inner core is made of a high-nickel positive electrode material; the organic-inorganic hybrid coating layer comprises a ring-opening copolymer of maleic anhydride and 1, 3-dioxolame, and Li3PO4 nanocrystals are embedded into the ring-opening copolymer of maleic anhydride and 1, 3-dioxolame in situ. According to the invention, a flexible and compact coating layer with ionic conductivity is constructed on the surface of the high-nickel positive electrode material, so that the problems of violent interface side reaction, large interface impedance and poor cycling stability existing between the high-nickel positive electrode material and sulfide solid electrolyte are solved; therefore, the electrochemical performance of the material in a sulfide all-solid-state lithium battery is remarkably improved.

The invention discloses a ternary material precursor, a ternary material and a preparation method, and belongs to the field of lithium ion battery positive electrode materials. The ternary material precursor is of a multi-layer composite structure and sequentially comprises a core layer, a first transition layer and a second transition layer from inside to outside, and all the layers are prepared by adopting the same ternary (nickel-cobalt-aluminum) system. Through reasonable design of the proportion and thickness of the ternary system of the core layer and the transition layer, the ternary material precursor gives consideration to the high-capacity characteristic of the high-nickel core and the stability of the shell, and the stable structure of the shell can effectively inhibit the structural change and interface side reaction of the high-nickel material in the charging and discharging process. The phenomena of particle cracking and shell layer falling are reduced, and the material shows excellent specific discharge capacity, good cycle performance and thermal stability when being used as a lithium ion battery positive electrode material.

The invention belongs to the technical field of resource recycling, and particularly relates to an energy storage bearing material and a preparation method thereof, and a structural electrode and a preparation method and application thereof. The energy storage bearing material provided by the invention has good bearing capacity and energy storage capacity and high compressive strength. The structural electrode provided by the invention has bearing capacity and energy storage capacity at the same time, and is high in compressive strength, high in cycle retention rate, good in stability and good in compatibility with buildings, and the retention rate of 5000 cycles is 93% or above. According to the structural electrode provided by the invention, the electric quantity is stored by adopting a double-electric-layer capacitance principle, and the structural electrode has good stability and durability; meanwhile, hidden dangers of liquid leakage and fire outbreak of a traditional pseudocapacitor can be avoided, the treatment problem caused by scrapping of a chemical battery can be solved, and environmental friendliness and sustainable development are achieved. The structural electrode provided by the invention can be applied to the field of energy development and utilization, and is wide in application scene.

This invention provides a lithium cobalt oxide cathode material coated with a lithium aluminum titanium phosphate composite, which has a core-shell structure, comprising a doped lithium cobalt oxide core material inside the core-shell structure and a coating layer formed on the surface of the doped lithium cobalt oxide core material; the chemical formula of the doped lithium cobalt oxide core material is: LiCo 1‑a‑b‑c Mg a Al b Ce c The coating layer comprises lithium aluminum titanium phosphate, cerium titanate, lithium cerium phosphate oxide, and lithium cerium phosphate. This invention's lithium aluminum titanium phosphate composite coating modified lithium cobalt oxide cathode material overcomes the defect of a sharp performance drop under high temperature and high pressure applications when lithium aluminum titanium phosphate is coated alone. The oxygen vacancies and coating structure provided by the composite coating layer of lithium aluminum titanium phosphate, cerium titanate, lithium cerium phosphate oxide, and lithium cerium phosphate enhance the structural continuity between the bulk phase and the coating layer, as well as the conductivity of the fast ion conductor, thereby enabling the material to maintain good cycle retention and capacity characteristics under high temperature and high pressure.

The application discloses a negative electrode sheet, a preparation method thereof, a lithium ion battery and an electric device, and belongs to the technical field of lithium ion batteries.The active material in the negative electrode active layer of the negative electrode sheet provided by the application comprises graphite and coated silicon-carbon, the coated silicon-carbon comprises a silicon-carbon base body and an artificial SEI coating layer, the total silicon mass fraction in the negative electrode active layer is controlled to be 2.5% to 17%, and the thickness of the artificial SEI coating layer is controlled to be 5nm to 25nm.When the total silicon mass fraction in the negative electrode active layer and the thickness of the artificial SEI coating layer are simultaneously limited in the above range, the battery can have a significant capacity advantage and effective inhibition of silicon volume expansion, and meanwhile, structural collapse caused by excessively high silicon content and the conduction efficiency of transition sacrificial lithium ions can be avoided.

The application provides a method for preparing a silicon-carbon material from photovoltaic waste silicon, comprising the following steps: S1, disassembling and cutting a decommissioned crystalline silicon photovoltaic panel to obtain a photovoltaic module; S2, soaking the photovoltaic module in an organic solvent to perform a degumming treatment, and peeling to obtain a silicon wafer; the organic solvent comprises at least one of terpinolene, terpineol, ethanol and polyvinylpyrrolidone; S3, performing ball milling and acid immersion treatment on the silicon wafer to obtain a silicon material; S4, mixing the silicon material with a carbon source material, and performing carbonization treatment to obtain a carbon-silicon material; S5, mixing the carbon-silicon material with raw materials for preparing an inorganic lithium salt, performing ball milling and calcination to obtain a modified carbon-silicon material; the raw materials for preparing the inorganic lithium salt comprise a lithium source and an anion source. The silicon wafer is peeled off efficiently and environmentally, then the carbon-silicon material is obtained by carbonization of the carbon source, and the surface of the carbon-silicon material is modified by in-situ construction of an inorganic lithium salt coating layer, so that the obtained electrode material has a high cycle retention rate.

The utility model provides a roll core structure and a battery. The roll core structure comprises a positive plate, a diaphragm and a negative plate, the positive plate, the diaphragm and the negative plate are jointly wound to form a roll core, the diaphragm is positioned between the positive plate and the negative plate, two flattening surfaces and two bending surfaces are formed on the outer side surface of the roll core, the flattening surfaces and the bending surfaces are alternately connected, and the roll core structure further comprises a binding colloid, the binding colloid is attached to the two bent surfaces respectively and completely covers the bent surfaces, and the length of the binding colloid is larger than or equal to the width of the positive plate. When the battery is used, the binding colloid ties the bending surface of the roll core structure, that is, the binding colloid ties the crease of the roll core, so that the effect of inhibiting deformation of the crease of the roll core is achieved, the problem of gap increase at the crease of the roll core is inhibited, the problem of black spot lithium precipitation at the crease of the roll core is further inhibited, the cycle retention rate of the battery is improved, and the service life of the battery is prolonged.

The invention discloses a Sb2O3 nano array-carbon-based composite material as well as a preparation method and application of the Sb2O3 nano array-carbon-based composite material. The preparation method comprises the following steps: (1) soaking the carbon-based material in an antimony salt solution; (2) annealing the soaked carbon-based material; (3) the annealed carbon-based material is subjected to a hydrothermal reaction in an epitaxial growth solution, and the Sb2O3 nano array is obtained on the carbon-based material; the epitaxial growth solution contains an antimony source, a template agent and a precipitator. The electrochemical performance is improved by improving the microstructure of the electrode material, and the composite material has good rate capability and cycling stability.

An object of the present invention is to provide a lithium metal composite oxide, when used as a positive electrode active material for a lithium secondary battery, capable of obtaining a lithium secondary battery having a high cycle retention rate, and a positive electrode active material for a lithium secondary battery, a positive electrode for a lithium secondary battery, and a lithium secondary battery in which the lithium metal composite oxide is used. This lithium metal composite oxide is a particulate lithium metal composite oxide, comprising first particles having a particle diameter equal to or less than a 50% cumulative volume particle size D50 of the lithium metal composite oxide and second particles having a particle diameter exceeding the D50, in which the D50 is 2 to 20 µm, an average particle strength Ps of the first particles is larger than an average particle strength PB of the second particles, and a standard deviation σS of the particle strength of the first particles is larger than a standard deviation σB of the particle strength of the second particles.

The invention relates to the technical field of lithium ion battery positive electrode materials, in particular to a solid electrolyte coated ternary positive electrode material and a preparation method and application thereof. The preparation method of the solid electrolyte coated ternary positive electrode material comprises the following steps: weighing a nickel-cobalt-manganese hydroxide precursor according to the stoichiometric ratio of the ternary material, and uniformly mixing the nickel-cobalt-manganese hydroxide precursor with a lithium source to obtain a mixture; placing the mixture in an oxygen-containing atmosphere, and carrying out first sintering treatment to obtain a ternary material; a LiB3H8 material is obtained; and uniformly mixing the ternary material with a LiB3H8 material, and carrying out secondary sintering treatment in an inert atmosphere to obtain the LiB3H8 / LiB3H8 composite material. According to the invention, the solid electrolyte LiB3H8 material is used as a coating layer, and meanwhile, after the ternary material and the LiB3H8 material are mixed and coated, surface coating fusion is carried out in an inert atmosphere, so that the diffusion rate of lithium ions between the positive electrode material and the electrolyte is improved, and the cycle retention rate, the specific capacity and the rate capability of the battery material are further improved.

The invention discloses a sodium positive electrode material, the sodium positive electrode material is of an O3 type, the chemical general formula is NaNixMn0. 5A0. 5xO2, x is more than or equal to 0.49 and less than 0.5, and A is selected from one or more of In, Sm, La and Ti. According to the scheme, a certain proportion of metal elements with relatively large ion radiuses are doped on the basis of an O3 type sodium positive electrode material, so that the interlayer spacing is enlarged, and the transmission rate and efficiency of Na < + > ions are improved; meanwhile, doped metal ions with a proper proportion are introduced into a crystal structure of the O3 type sodium positive electrode material, so that the cycle retention rate of the sodium ion battery positive electrode material can be effectively improved.

The invention discloses a diaphragm and a preparation method thereof, a battery and electric equipment. The diaphragm comprises a base membrane, components of the base membrane comprise a polymer material and inorganic material particles, the polymer material forms a polymer matrix, and the inorganic material particles are dispersed in the polymer matrix.

The invention discloses a preparation method for preparing a ternary material by using a nickel-iron alloy and the ternary material, and belongs to the technical field of ternary material preparation, and the preparation method comprises the following steps: S1, carrying out crushing and roasting pretreatment on the nickel-iron alloy, then carrying out acid leaching in a sulfuric acid solution, and filtering and collecting a mixed solution; s2, sequentially adding a sodium sulfide solution and a sodium fluoride solution into the mixed solution, filtering, and collecting a refined solution; s3, supplementing a cobalt source and a manganese source into the refined solution, and adjusting the molar ratio of Ni < 2 + > to Co < 2 + > to Mn < 2 + > in the solution to be x: y: (1-x-y), x = 0.6-0.8, and y = 0.1-0.2; adjusting the pH value of the refined solution to 10.5-11.5, filtering and collecting a precipitate to obtain a ternary precursor; and S4, uniformly mixing the ternary precursor, a lithium source and a doping agent to obtain a mixture which is yttrium salt and zirconium salt, and sintering the mixture to obtain the ternary material.